Abstract: A flow probe has been described which includes a sensor housing and a coupling member. The sensor housing with one or more sensors mated together with the coupling member form the flow probe. The sensor housing accepts a variety of different sized coupling members to form flow probes of different sizes. The sensor housing is adapted to house one or more transducers. Additionally, a version of the flow probe includes strategically located positioning elements for ease in placement and retrieval of the flow probe.

Abstract: A flow probe has been described which includes a sensor housing and a coupling member. The sensor housing with one or more sensors mated together with the coupling member form the flow probe. The sensor housing accepts a variety of different sized coupling members to form flow probes of different sizes. The sensor housing is adapted to house one or more transducers. Additionally, a version of the flow probe includes strategically located positioning elements for ease in placement and retrieval of the flow probe.

Abstract: A system and method obtains a respiration parameter of an animal or human, such as respiratory rate, from a blood pressure, volumetric blood flow, blood velocity or stroke volume signal from a sensor for the animal or human. Specifically, the signal is processed to develop an amplitude versus time waveform. A sequence of selected features derived from individual cardiac cycles of the amplitude versus time waveform over a selected time interval are extracted from the developed amplitude versus time waveform. A mathematical model is fitted to the extracted sequence of selected features to yield a fitted mathematical model. The physiologic parameter information is computed from the fitted mathematical model.

Abstract: A strobed blood flow meter provides periodic measurements of blood flow velocity or volumetric blood flow over a cardiac cycle at reduced average power consumption, which is advantageous for reducing battery size, and extending device battery life, such as in an implantable application. Continuous wave Doppler, pulsed Doppler, laser Doppler, transit time, electromagnetic flow, and thermal dilution techniques are included. Strobing provides higher level excitation during active periods, which improves signal-to-noise ratio, and provides a low power standby mode during an idle time between active periods. The invention may be used for chronic or acute applications. Doppler or other signals may be telemetered from an implanted portion of the flow meter for further signal processing to extract velocity or volumetric flow. Alternatively, such signal processing is also implanted, such that the velocity signal can be telemetered to an remote monitor.

Abstract: A method for estimating fluid flow in a conduit using a probe with four transducers is provided. The method includes generating two transit time measurements and compensating for an error angle in the transit time measurements using a predetermined compensation factor. The method further includes generating a flow measurement and estimating fluid flow based on the flow measurement.

Abstract: A strobed blood flow meter provides periodic measurements of blood flow velocity or volumetric blood flow over a cardiac cycle at reduced average power consumption, which is advantageous for reducing battery size, and extending device battery life, such as in an implantable application. Continuous wave Doppler, pulsed Doppler, laser Doppler, transit time, electromagnetic flow, and thermal dilution techniques are included. Strobing provides higher level excitation during active periods, which improves signal-to-noise ratio, and provides a low power standby mode during an idle time between active periods. The invention may be used for chronic or acute applications. Doppler or other signals may be telemetered from an implanted portion of the flow meter for further signal processing to extract velocity or volumetric flow. Alternatively, such signal processing is also implanted, such that the velocity signal can be telemetered to an remote monitor.

Abstract: A method for detecting a phase difference between first and second input signals is provided. The method includes modulating a duty cycle of first and second intermediate signals from a first duty cycle based on the phase difference between the first and second input signals. The method further includes creating a differential output signal based on the modulated duty cycles of the first and second intermediate signals that is related to the phase difference between the first and second input signals.

Abstract: A method for detecting a phase difference is provided. The method includes selecting first and second input signals from a plurality of pairs of input signals. The method further includes modulating a duty cycle of first and second intermediate signals from a first duty cycle based on a phase difference between the first and second input signals. The method also includes creating a differential signal based on the modulated duty cycles of the first and second intermediate signals that is related to the phase difference between the first and second input signals.

Abstract: A flow probe has been described which includes a sensor housing and a coupling member. The sensor housing with one or more sensors mated together with the coupling member form the flow probe. The sensor housing accepts a variety of different sized coupling members to form flow probes of different sizes. The sensor housing is adapted to house one or more transducers. Additionally, a version of the flow probe includes strategically located positioning elements for ease in placement and retrieval of the flow probe.

Abstract: A system and method obtains a respiration parameter of an animal or human, such as respiratory rate, from a blood pressure, volumetric blood flow, blood velocity or stroke volume signal from a sensor for the animal or human. Specifically, the signal is processed to develop an amplitude versus time waveform. A sequence of selected features derived from individual cardiac cycles of the amplitude versus time waveform over a selected time interval are extracted from the developed amplitude versus time waveform. A mathematical model is fitted to the extracted sequence of selected features to yield a fitted mathematical model. The physiologic parameter information is computed from the fitted mathematical model.

Abstract: A system and method obtains a respiration parameter of an animal or human, such as respiratory rate, from a blood pressure, volumetric blood flow, blood velocity or stroke volume signal from a sensor for the animal or human. Specifically, the signal is processed to develop an amplitude versus time waveform. A sequence of selected features derived from individual cardiac cycles of the amplitude versus time waveform over a selected time interval are extracted from the developed amplitude versus time waveform. A mathematical model is fitted to the extracted sequence of selected features to yield a fitted mathematical model. The physiologic parameter information is computed from the fitted mathematical model.

Abstract: A strobed blood flow meter provides periodic measurements of blood flow velocity or volumetric blood flow over a cardiac cycle at reduced average power consumption, which is advantageous for reducing battery size, and extending device battery life, such as in an implantable application. Continuous wave Doppler, pulsed Doppler, laser Doppler, transit time, electromagnetic flow, and thermal dilution techniques are included. Strobing provides higher level excitation during active periods, which improves signal-to-noise ratio, and provides a low power standby mode during an idle time between active periods. The invention may be used for chronic or acute applications. Doppler or other signals may be telemetered from an implanted portion of the flow meter for further signal processing to extract velocity or volumetric flow. Alternatively, such signal processing is also implanted, such that the velocity signal can be telemetered to an remote monitor.

Abstract: A strobed blood flow meter provides periodic measurements of blood flow velocity or volumetric blood flow over a cardiac cycle at reduced average power consumption, which is advantageous for reducing battery size, and extending device battery life, such as in an implantable application. Continuous wave Doppler, pulsed Doppler, laser Doppler, transit time, electromagnetic flow, and thermal dilution techniques are included. Strobing provides higher level excitation during active periods, which improves signal-to-noise ratio, and provides a low power standby mode during an idle time between active periods. The invention may be used for chronic or acute applications. Doppler or other signals may be telemetered from an implanted portion of the flow meter for further signal processing to extract velocity or volumetric flow. Alternatively, such signal processing is also implanted, such that the velocity signal can be telemetered to an remote monitor.

Abstract: A strobed blood flow meter provides periodic measurements of blood flow velocity or volumetric blood flow over a cardiac cycle at reduced average power consumption, which is advantageous for reducing battery size, and extending device battery life, such as in an implantable application. Continuous wave Doppler, pulsed Doppler, laser Doppler, transit time, electromagnetic flow, and thermal dilution techniques are included. Strobing provides higher level excitation during active periods, which improves signal-to-noise ratio, and provides a low power standby mode during an idle time between active periods. The invention may be used for chronic or acute applications. Doppler or other signals may be telemetered from an implanted portion of the flow meter for further signal processing to extract velocity or volumetric flow. Alternatively, such signal processing is also implanted, such that the velocity signal can be telemetered to an remote monitor.